从未存在过的化物:重新审视施劳泽的"化物"
David C Lacy1, Gerri M Roberts1, Jonas C Peters1
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.
Journal of the American Chemical Society
|March 24, 2015
概括
一个重新研究的复合物,以前被认为是化物,实际上是 (II) 种. 这一发现影响了使用cobaloximes的演化反应 (HER) 的机制研究.
科学领域:
- 无机化学 无机化学
- 电触媒溶解是一种电触媒.
- 进化反应 (HER) 是一种
背景情况:
- -二甲基氧胺 (dmg) 复合物是HER研究的关键电催化剂.
- 施劳泽对所谓的化复合物的分离,为HER.中的Co (III) -H中间体提供了支持.
- 这种所谓的化物在科巴洛キシ化物和HER催化物的研究中得到了广泛的引用.
研究的目的:
- 为了重新评估施劳泽的素稳定-dmg复合物的结构.
- 为了澄清与进化反应 (HER) 机制相关的物种的身份.
- 为了纠正错误地将质子NMR信号归因于水化物种.
主要方法:
- 通过X射线晶体学来确定固态结构.
- 光谱分析,包括质子NMR.
- 合成的-dmg复合物和杂质的表征.
主要成果:
- 以前被确定为 (III) 化物的复合物被重新分配为 (II) 复合物,[Co (II) (dmgH) 2P (nBu) 3].
- 这种(II) 复合物在固态中二元化,形成无支的Co-Co键.
- 一种被误认为是化物的偏磁性杂质,在 -5.06 ppm时呈现出质子NMR信号.
结论:
- 广泛引用的"基胺"不是化物,而是 (II) 复合物.
- 这种结构的重新分配对于理解由cobaloximes催化的演化反应 (HER) 的机制至关重要.
- 这些发现需要重新评估以前的机械模型,这些模型依赖于这种特定的化的存在.
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